Béla the Blind was King of Hungary and Croatia from 1131 to 1141. He was blinded along with his rebellious father Álmos on the order of Álmos's brother, King Coloman of Hungary. Béla grew up in monasteries during the reign of Coloman's son Stephen II. The childless king arranged Béla's marriage with Helena of Rascia, who would become her husband's co-ruler throughout his reign.

Béla was crowned king at least two months after the death of Stephen II, implying that his accession to the throne did not happen without opposition. Two violent purges were carried out among the partisans of his predecessors to strengthen Béla's rule. King Coloman's alleged son Boris tried to dethrone Béla but the king and his allies defeated the pretender's troops in 1132. In the second half of Béla's reign, Hungary adopted an active foreign policy. Bosnia and Split seem to have accepted Béla's suzerainty around 1136.